Its simple…Traffic Signals and streetlights cost money like a set could cost as much as $10,000.00 or more. Streetlights burns “juice” and add carbon emissions. Yet we have thousands of accidents at intersections by people running red lights and going around RR crossing gates. What if we could install a virtual view screen that would show traffic signals that would reflect off the windsheild? If the driver ignores the signal the cars brakes apply immediately. A simple transponder would cost less then 100.00 on poles at intercections or use the cell tower network. This would be something between self driving cars and PTC for automobles. There have been stuff like this in the works since the 1970s but for the most part the US traffic signal system has not changed since the 1940s.
That $100 transponder has to tell oncoming vehicles what they can do, and in which lane, and depending on which way they are travelling.
In addition, every vehicle has to have a compatible device that is capable of knowing which way the vehicle is travelling, and which lane it’s it. That’s a problem the railroads are still working on as it applies to multiple tracks.
Sometimes I am amazed at the logic necessary to not only make a single intersection work, but at what’s involved to tie together multiple intersections along a busy street/road to maximize traffic flow. Tying all that together with the devices in the vehicles would make one’s head spin.
Then there are the hundreds of contingencies involved. What if a vehicle is forced to stop by the system, but that stop ends up in the middle of the intersection? And that’s just for starters.
In Michigan, if not most states, we have the right turn on red after stop law. How would your system know that a car “running the red light” was doing that perfectly legal move?
But if you are serious about this, then get yourself up to date on the driverless cars that are in the news every day. They have to do exactly what you propose.
All of this push with PTC causes me to think it is a test for driverless vehicles. Cab signals work very well because they do not incorporate the multitude of eventualities that present themselves in vehicular traffic - only the condition of the particular block (segment of track between signals) a train occupies.
All states allow right turn on red after stopping unless signs posted otherwise. (We have some cities that have signs that prohibit the turn “when children are present.”)
Some techies don’t want future generations of driverless cars to even have steering wheels or other controls.
Jeff
So, if trolls get caught out in sunlight…oh, wait, that’s ogres, isn’t it?
Never mind…….
And how about the “Michigan Left?”
Not to be confused with the Pittsburgh Left.
Ed, you had it right the first time–ordinary trolls turn to stone when sunlight hits them. But Sauron (in the Lord of the Rings trilogy) created trolls that were not so affected by sunlight.
Oh… ogres. Phew. That’s not what I read the first time and was kind of confused.
Michigan left? You mean the turn right then make a U-turn a quarter mile down the street? I always called that a DEE-troit left.
Salt Lake County streets have that kindof turn, too. I found them quite annoying. I’m glad I don’t drive any more.
Considering the number of places where a car can join the flow of traffic, I can’t see the cost of a “pole and transponder” at every one of those being cheaper than a stoplight at major intersection and the ultimate computer controlling a car (a human at the wheel) for all the other unrecorded “intersections”.
As for using the cell tower system for all the communications… have you ever tried to use a cell phone during a major widspread emergency? Now, stick several thousand cars on that network and I doubt if the car would get updates about traffic conditions every few blocks and would know nothing about changing conditions between.